QuestionIs there an association between antidepressants and hip fracture?

FindingsIn this population-based, matched cohort study of 408 144 individuals aged 65 years and older, the association between antidepressant drug use and hip fracture was present in the year before and year after the initiation of treatment. The pattern was consistent for all studied antidepressants and subgroups.

MeaningThese findings raise questions about the association between antidepressant drug use and hip fracture that requires further analysis in treatment studies.

Abstract

ImportanceTreatment with antidepressants has been associated with hip fracture. This association could restrict the treatment options, especially in older patients.

ObjectiveTo investigate the association between antidepressant drug treatment and hip fracture starting 1 year before the initiation of treatment.

Design, Setting, and ParticipantsIn this nationwide cohort study, 204 072 individuals in the Prescribed Drugs Register of Sweden’s National Board of Health and Welfare aged 65 years or older who had a prescription of antidepressants filled between July 1, 2006, and December 31, 2011, were matched by birth year and sex to 1 control participant who was not prescribed antidepressants (for a total of 408 144 people in the register). Outcome data were collected from 1 year before to 1 year after the index date (date of prescription being filled). Data analysis was performed from July 1, 2005, to December 31, 2012.

ExposuresFirst filled prescription of an antidepressant drug.

Main Outcomes and MeasuresIncident hip fractures occurring in the year before and year after initiation of antidepressant therapy were registered. Associations were investigated using multivariable conditional logistic regression models and flexible parametric models.

ResultsOf the 408 144 people in the register who were included in the study, 257 486 (63.1%) were women, with a mean (SD) age of 80.1 (7.2) years. Antidepressant users sustained more than twice as many hip fractures than did nonusers in the year before and year after the initiation of therapy (2.8% vs 1.1% and 3.5% vs 1.3%, respectively, per actual incidence figures). In adjusted analyses, the odds ratios were highest for the associations between antidepressant use and hip fracture 16 to 30 days before the prescription was filled (odds ratio, 5.76; 95% CI, 4.73-7.01). In all separate analyses of age groups, of men and women, and of individual antidepressants, the highest odds ratios were seen 16 to 30 days before initiation of treatment, and no clear dose-response relationship was seen.

Conclusions and RelevanceThe present study found an association between antidepressant drug use and hip fracture before and after the initiation of therapy. This finding raises questions about the association that should be further investigated in treatment studies.